The present invention relates to the field of satellite communications. More particularly, the present invention relates to systems and methods for automatically setting-up antennas for very small aperture satellite terminals.
Currently in the industry, to position an Antenna, a skilled technician is required to position the Antenna manually by use of certain positioning equipment. This equipment is separate from and external to the Antenna. This currently used manual mechanism requires a professional/skilled person to attend the location where an Antenna is to be installed and position the antenna, representing significant resources and costs. Further, this complex procedure is beyond the capabilities of the average homeowner prohibiting the homeowner from performing a self installation. Hence there is a need for a low cost and simple system and method which enables the average homeowner to install satellite equipment.
In order to overcome the disadvantages of conventional systems, there are a number of objects and associated aspects of the present invention.
Aspects of the present invention include a mechanism for automatically positioning/directing satellite antennas at an end user location towards a satellite with which it is to communicate. Without limiting the foregoing, this mechanism can be used for antennas which comprise part of a satellite-based VSAT communications system for communication.
Other aspects of the invention include the automatic positioning/directing of an Antenna without the need for a skilled person to attend the Antenna installation site in order to position the Antenna. Further aspects of the invention include allowing a consumer/end-user to direct/position an Antenna without any requirement for input from a skilled technician. This represents significant cost savings and is especially significant for satellite-based VSAT communications networks designed to be installed by a homeowner or in home based applications.
Further aspects of the invention may include systems and methods which enable an Antenna to be automatically positioned/directed to a predetermined position. The systems and methods may include applying the use of characteristics of symmetry of mutually exclusive orthogonal axes. In these embodiments, by using the symmetry of the antenna main beams, the ideal direction of the antenna can be attained (this ideal direction is known as xe2x80x9cmaximum gain pointxe2x80x9d) and, at the same time, maximum cross-polarization may be achieved. The cross polarization may be required in order not to interfere with the orthogonal polarization.
The positioning of an Antenna towards a satellite typically requires a high degree of accuracy. In order for an unskilled person to attain this high degree of accuracy, the systems and methods contained herein may include:
1. a maximum gain for receiving and transmitting satellite communications;
2. a cross-polarization for the receiving frequencies and particularly for transmitting frequencies. The cross-polarization may be advantageous in that the system will not interfere with orthogonal polarization; and
3. maintaining symmetry of the receiving and the transmission beams, and particularly the main beam, for receiving and transmitting communication, so as not to interfere with satellite communication of other satellites.
The above features may be utilized individually or in combination. Where used in combination, the above features have the advantage of minimizing the positioning/direction error.
In aspects of the invention, the system and method may position the Antenna on three mutually exclusive orthogonal planes. These typically include:
(i) the azimuth plane;
(ii) the elevation plane; and
(iii) the polarization plane.
In still further aspects of the invention, the system and method may include three sub-mechanisms each of which may contain instructions for mechanical and electronic positioning of the Antenna towards the satellite. To do this with the degree of accuracy required for enabling satellite communication, an accuracy greater than {fraction (1/10)}th of the beam width of the Antenna may be required.
In other aspects of the invention, the system and method may comprises two principal components:
(a) an indoor unit (IDU), which may include a satellite receiver, a telemetric transmission (feed back on the strength of the signal), and supply of voltage to a control system (which may be contained in the ODU) and which may control a drive motor and/or an electronic search device; and
(b) an outdoor unit (ODU), which may include a supervisory unit, a motor, and a control unit (e.g., an electronic control unit). The outdoor unit is preferably configured to conduct a search in the three orthogonal planes which may facilitate positioning the Antenna with a high degree of accuracy. This is according to the messages received from indoor unit telemetry.
By use of the symmetry principle of the receiving beam and the polarization plane, a search may be conducted for the symmetry in each one of the said planes. The symmetry principle may be applied to the search of the three dB points (xe2x88x923 dB) for each one of the orthogonal planes. By locating a signal from the satellite at a point of symmetry, it may be possible to find the point at which two points of symmetry are of the highest possible values. If we add further points of symmetry, such as the xe2x88x925 dB point, it is possible to improve the positioning ability of the systems and methods described herein and obtain a more accurate positioning of the main beam. As the number of symmetry points increases, so does the accuracy of the systems and methods described herein.
In still further aspects of the invention, the stages for implementing the systems and methods described herein may include:
1. a manual positioning of the Antenna in the three planes described above according to the satellite""s position and the Antenna""s geographic location, by using a compass. These measurements can be obtained by using known tables and known parameters.
2. operating the automatic searching components which may be configured to search for the symmetry in the three planes mentioned above. This procedure can be repeated a number of times until attainment of an acceptable value.
3. the system may then be configured to xe2x80x9cinformxe2x80x9d the user whether or not the search was done successfully.
Typically in satellite-based VSAT communications networks, a central data processing center may communicate with hundreds, thousands, tens of thousand, or even hundreds or thousands of remote sites. At each of these remote sites, an Antenna (among other things) needs to be installed. Under currently available technology skilled technicians are required to attend each remote sites to position an Antenna, representing significant costs. The systems and methods described herein eliminate this requirement.
These and other features of the invention will be apparent upon consideration of the following detailed description of preferred embodiments. Although the invention has been defined using the appended claims, the invention may include one or more aspects of the embodiments described herein including the elements and steps described in any combination or sub combination. For example, it is intended that each of the above aspects of the invention may be used individually and/or in combination with one or more other aspects of the invention defined above, in the drawings, and/or in connection with the detailed description below. Accordingly, there are any number of alternative combinations for defining the invention, which incorporate one or more elements from the specification, including the description, claims, aspects of the invention, and/or drawings, in various combinations or sub combinations. Accordingly, it will be apparent to those skilled in satellite communication art in view of the present specification, that alternate combinations and sub combinations of one or more aspects of the present invention, either alone or in combination with one or more elements and/or steps defined herein, may constitute alternate aspects of the invention. It is intended that the written description of the invention contained herein cover all such modifications and alterations.